Light outcoupling efficiency of phosphorescent oleds by mixing horizontally aligned fluorescent emitters

ABSTRACT

Organic light emitting devices (OLEDs) with emissive layers containing both phosphorescent Pt complexes and fluorescent emitters, are described. The devices presented employ both fluorescent and phosphorescent Pt complexes in order to redistribute the excited states to primarily reside on known stable fluorescent emitters to achieve high device operational stability but maintain the high efficiency characteristic of phosphorescent OLEDs.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional ApplicationNo. 62/796,704, filed Jan. 25, 2019, which is incorporated by referenceherein in its entirety.

BACKGROUND OF THE INVENTION

Organic light emitting devices (OLED) are typically multilayer deviceswhich upon an applied voltage are capable emitting light from theradiative relaxation of an excited state located on an organic material.OLEDs have found widespread application as an alternative to LCDs forhandheld devices or flat panel displays. Furthermore, OLEDs have shownpromise as next generation solid state white lighting, use in medicaldevices, and as infrared emitters for communication applications. Theuse of organic materials presents a number of unique benefits including:compatibility with flexible substrates, capabilities for large scaleproduction, and simplified tuning of the emission properties throughmolecular modification.

A typical OLED device consists of at least one transparent electrodethrough which the light emits. For example OLEDs which emit through thebottom substrate typically contain a transparent conductive oxidematerial, such as indium tin oxide, as an anode, while at the cathode areflective metal is typically used. Alternatively, devices may emit fromthe top through a thin metal layer as the cathode while having an eitheropaque or transparent anode layer. In this way it is possible to havedual emission from both top and bottom if such a device is so desiredand furthermore it is possible for these OLEDs to be transparent.Sandwiched between the electrodes is typically a multilayer organicstack typically a single layer of hole-transporting materials (HTL), asingle layer of emissive materials (EML) including emitters and hosts, asingle layer of electron-transporting materials (ETL) and a layer ofmetal cathode, shown in FIG. 1. For each of the transport layers caremust be taken to optimize the separate process of facilitating chargeinjection, have efficient charge transport, and confining the chargesand excitons in a specified emissive region (typically the emissivelayer). Such a process can be achieved through either a single materialor through a multilayer stack which may separate the injection,transport, charge confining, and exciton confining tasks. The emissivelayer may be composed of a single emissive materials, a single emissivematerial dispersed in a host matrix material, multiple emissivematerials dispersed in a host matrix, or any number of emissivematerials dispersed in multiple host materials. The host materials muchbe chosen carefully to not quench the excited state of the emitter aswell as provide appropriate distribution of charges and excitons withinthe emissive layer. The emission color of the OLED is determined by theemission energy (optical energy gap) of emitters.

Light is generated in OLEDs through the formation of excited states fromseparately injected electrons and holes to form an exciton, located onthe organic material. Due to the uncorrelated nature of the injectedcharges excitons with total spin of 0 and 1 are possible. Spin 0excitons are denoted singlets while spin 1 excitons are denotedtriplets, reflecting their respective degeneracies. Due to the selectionrules for radiative transitions, the symmetry of the excited state andthe ground state must be the same. Since the ground state of mostmolecules are antisymmetric, radiative relaxation of the symmetrictriplet excited state is typically disallowed. As such, emission fromthe triplet state, called phosphorescence, is very slow and thetransition probability is very low. However, emission from the singletstate, called fluorescence can be very rapid and consequently veryefficient. Nevertheless, statistically there is only 1 singlet excitonfor every 3 triplet excitons formed. There are very few fluorescentemitters which exhibit emission from the triplet state at roomtemperature, so 75% of the generated excitons are wasted in mostfluorescent emitters. However, emission from the triplet state can befacilitated through spin orbit coupling which incorporates a heavy metalatom in order to perturb the triplet state and add in some singletcharacter to and achieve a higher probability of radiative relaxation.

SUMMARY OF THE INVENTION

According to one embodiment, an organic light emitting device (OLED) isprovided. The OLED comprises an anode; a cathode; and at least oneorganic layer disposed between the anode and the cathode; wherein the atleast one organic layer includes a phosphorescent/MADF emitter and afluorescent emitter. In one embodiment, the phosphorescent/MADF emitteris a compound having Formula I or Formula II;

wherein A is an accepting group comprising one or more of the followingstructures, which can optionally be substituted:

wherein D is a donor group comprising of one or more of the followingstructures, which can optionally be substituted:

wherein N in Formula I or II comprises one or more of the followingstructures, which can optionally be substituted:

wherein N in Formula I or II comprises one or more of the followingstructures, which can optionally be substituted:

wherein each of a⁰, a¹, and a² independently is present or absent, andif present, comprises a direct bond and/or linking group comprising oneor more of the following:

wherein each occurrence of a is independently substituted orunsubstituted N or substituted or unsubstituted C;

wherein b¹ and b² independently is present or absent, and if present,comprises a linking group comprising one or more of the following:

wherein each occurrence of X is independently B, C, N, O, Si, P, S, Ge,As, Se, Sn, Sb, or Te;

wherein Y is O, S, S═O, SO₂, Se, N, NR³, PR³, RP═O, CR¹R², C═O, SiR¹R²,GeR¹R², BH, P(O)H, PH, NH, CR¹H, CH₂, SiH₂, SiHR¹, BH, or BR³,

wherein each of R, R¹, R², and R³ independently is hydrogen, aryl,cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl,alkynyl, deuterium, halogen, hydroxyl, thiol, nitro, cyano, amino, amono- or di-alkylamino, a mono- or diaryl amino, alkoxy, aryloxy,haloalkyl, aralkyl, ester, nitrile, isonitrile, alkoxycarbonyl,acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino,sulfamoyl, carbamoyl, alkylthio, sulfinyl, ureido, phosphoramide,mercapto, sulfo, carboxyl, hydrazino, substituted silyl, orpolymerizable, or any conjugate or combination thereof,

wherein n is a number that satisfies the valency of Y; and

wherein M is platinum, palladium, nickel, manganese, zinc, gold, silver,copper, iridium, rhodium, and/or cobalt.

In one embodiment, the emitting dipole of the fluorescent emitter ishorizontally oriented. In one embodiment, the ratio of organic dipolesin at least one organic layer is greater than 0.7

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description of preferred embodiments will bebetter understood when read in conjunction with the appended drawings.For the purpose of illustration, there are shown in the drawingsembodiments which are presently preferred. It should be understood,however, that the disclosure is not limited to the precise arrangementsand instrumentalities of the embodiments shown in the drawings.

FIG. 1 is a schematic diagram of an exemplary organic light emittingdevice.

FIG. 2 is a diagram of the energy transfer process inside of emissivelayer for the proposed OLEDs with phosphorescent emitter as donor andfluorescent emitter as acceptor.

FIG. 3 is a diagram of the energy transfer process inside of emissivelayer for the proposed phosphorescent OLEDs with MADF emitter as donorand fluorescent emitter as acceptor.

FIG. 4 is a schematic diagram of an exemplary light emitting devicestructure comprising a mixed layer of a phosphorescent/MADF donormaterial and a fluorescent emitter within a host matrix.

FIG. 5 is a schematic diagram of an exemplary light emitting devicestructure comprising alternating fluorescent and phosphorescent/MADFdoped layers.

FIGS. 6A to 6C depict the benefit of horizontal dipole orientation. FIG.6A is a schematic illustration of random emitting dipole orientation.FIG. 6B is a schematic illustration of controlled horizontally emittingdipole orientation. FIG. 6C is a contour plot of the maximum achievableEQE possessing a certain PLQY and ratio of the horizontal dipoles.

FIGS. 7A to 7C present data for an exemplary organic light emittingdevice with a general device structure ofITO/HATCN/NPD/Tris-PCz/EML/mCBT/BPyTP/LiF/Al, where EMLs are (1) 20%PtNON:mCBP (5 nm)/10% PtNON:mCBP (5 nm)/5% PtNON:mCBP (5 nm); (2) 20%PtNON:mCBP (5 nm)/2% DABNA-2:mCBP (2 nm)/10%/PtNON:mCBP (5 nm)/2%DABNA-2:mCBP (2 nm)/5% PtNON:mCBP (5 nm). FIG. 7A is a plot depictingcurrent-voltage characteristics. FIG. 7B is a plot of theelectroluminescent spectra of devices (1) and (2). FIG. 7C is a plot ofexternal quantum efficiency (EQE) vs. brightness for the two exemplarydevices.

FIG. 8 is a plot of angle-dependent PL intensity of p-polarized light at470 nm from 25 nm 2%-doped DABNA-2:mCBP film.

FIGS. 9A to 9D present data for an exemplary organic light emittingdevice with a general device structure ofITO/HATCN/NPD/TAPc/EML/DPPS/BmPyPB/LiF/Al, where EMLs are (1) 10%PtNON:26mCPy; (2) 10% PtNON:1% FL1:26mCPy and (3) 10% PtNON:2%FL1:26mCPy. FIG. 9A is a plot of external quantum efficiency (EQE) vs.brightness. FIG. 9B is a plot of current-voltage characteristics. FIG.9C is a plot of the electroluminescent spectra of the devices. FIG. 9Dis a schematic showing the structure of the devices.

FIGS. 10A to 10D present data for an exemplary organic light emittingdevice with a general device structure of ITO/HATCN(10 nm)/NPD (40nm)/TAPC (10 nm)/26mCPy:10% PtNON (4 nm)/26mCPy:2% FLB1 (2 nm)/26mCPy:10% PtNON (4 nm)/26mCPy:2% FLB1 (2 nm)/26mCPy: 10% PtNON (4 nm)/DPPS (10nm)/BmPyPB(40 nm)/LiF/Al. FIG. 10A is a plot of external quantumefficiency (EQE) vs. brightness. FIG. 10B is a plot of current-voltagecharacteristics. FIG. 10C is a plot of the electroluminescent spectra ofthe devices relative to a single layer standard.

DETAILED DESCRIPTION Definitions

It is to be understood that the figures and descriptions herein havebeen simplified to illustrate elements that are relevant for a clearunderstanding of the present disclosure, while eliminating, for thepurpose of clarity, many other elements found in the art related tophosphorescent organic light emitting devices and the like. Those ofordinary skill in the art may recognize that other elements and/or stepsare desirable and/or required in implementing the devices disclosedherein. However, because such elements and steps are well known in theart, a discussion of such elements and steps is not provided herein. Thedisclosure herein is directed to all such variations and modificationsto such elements and methods known to those skilled in the art.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this disclosure pertains. Although any methods,materials and components similar or equivalent to those described hereincan be used in the practice or testing of the disclosed devices andcompositions, the preferred methods, and materials are described.

As used herein, each of the following terms has the meaning associatedwith it in this section.

The articles “a” and “an” are used herein to refer to one or to morethan one (i.e., to at least one) of the grammatical object of thearticle. By way of example, “an element” means one element or more thanone element.

“About” as used herein when referring to a measurable value such as anamount, a temporal duration, and the like, is meant to encompassvariations of ±20%, ±10%, ±5%, ±1%, or ±0.1% from the specified value,as such variations are appropriate.

Throughout this disclosure, various aspects can be presented in a rangeformat. It should be understood that the description in range format ismerely for convenience and brevity and should not be construed as aninflexible limitation. Accordingly, the description of a range should beconsidered to have specifically disclosed all the possible subranges aswell as individual numerical values within that range. For example,description of a range such as from 1 to 6 should be considered to havespecifically disclosed subranges such as from 1 to 3, from 1 to 4, from1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well asindividual numbers within that range, for example, 1, 2, 2.7, 3, 4, 5,5.3, 6 and any whole and partial increments therebetween. This appliesregardless of the breadth of the range.

Disclosed are the components to be used to prepare the compositions ofthe disclosure as well as the compositions themselves to be used withinthe methods disclosed herein. These and other materials are disclosedherein, and it is understood that when combinations, subsets,interactions, groups, etc. of these materials are disclosed that whilespecific reference of each various individual and collectivecombinations and permutation of these compounds cannot be explicitlydisclosed, each is specifically contemplated and described herein. Forexample, if a particular compound is disclosed and discussed and anumber of modifications that can be made to a number of moleculesincluding the compounds are discussed, specifically contemplated is eachand every combination and permutation of the compound and themodifications that are possible unless specifically indicated to thecontrary. Thus, if a class of molecules A, B, and C are disclosed aswell as a class of molecules D, E, and F and an example of a combinationmolecule, A-D is disclosed, then even if each is not individuallyrecited each is individually and collectively contemplated meaningcombinations, A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are considereddisclosed. Likewise, any subset or combination of these is alsodisclosed. Thus, for example, the sub-group of A-E, B-F, and C-E wouldbe considered disclosed. This concept applies to all aspects of thisapplication including, but not limited to, steps in methods of makingand using the compositions disclosed herein. Thus, if there are avariety of additional steps that can be performed it is understood thateach of these additional steps can be performed with any specificembodiment or combination of embodiments of the methods disclosedherein.

As referred to herein, a linking atom or a linking group can connect twogroups such as, for example, an N and C group. The linking atom canoptionally, if valency permits, have other chemical moieties attached.For example, in one aspect, an oxygen would not have any other chemicalgroups attached as the valency is satisfied once it is bonded to twogroups (e.g., N and/or C groups). In another aspect, when carbon is thelinking atom, two additional chemical moieties can be attached to thecarbon. Suitable chemical moieties includes, but are not limited to,hydrogen, hydroxyl, alkyl, alkoxy, ═O, halogen, nitro, amine, amide,thiol, aryl, heteroaryl, cycloalkyl, and heterocyclyl.

The term “cyclic structure” or the like terms used herein refer to anycyclic chemical structure which includes, but is not limited to, aryl,heteroaryl, cycloalkyl, cycloalkenyl, and heterocyclyl.

As used herein, the term “substituted” is contemplated to include allpermissible substituents of organic compounds. In a broad aspect, thepermissible substituents include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, and aromatic and nonaromaticsubstituents of organic compounds. Illustrative substituents include,for example, those described below. The permissible substituents can beone or more and the same or different for appropriate organic compounds.For purposes of this disclosure, the heteroatoms, such as nitrogen, canhave hydrogen substituents and/or any permissible substituents oforganic compounds described herein which satisfy the valences of theheteroatoms. This disclosure is not intended to be limited in any mannerby the permissible substituents of organic compounds. Also, the terms“substitution” or “substituted with” include the implicit proviso thatsuch substitution is in accordance with permitted valence of thesubstituted atom and the substituent, and that the substitution resultsin a stable compound, e.g., a compound that does not spontaneouslyundergo transformation such as by rearrangement, cyclization,elimination, etc. It is also contemplated that, in certain aspects,unless expressly indicated to the contrary, individual substituents canbe further optionally substituted (i.e., further substituted orunsubstituted).

The term “alkyl” as used herein is a branched or unbranched saturatedhydrocarbon group of 1 to 24 carbon atoms, such as methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl,isopentyl, s-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl,dodecyl, tetradecyl, hexadecyl, eicosyl, tetracosyl, and the like. Thealkyl group can be cyclic or acyclic. The alkyl group can be branched orunbranched. The alkyl group can also be substituted or unsubstituted.For example, the alkyl group can be substituted with one or more groupsincluding, but not limited to, alkyl, cycloalkyl, alkoxy, amino, ether,halide, hydroxy, nitro, silyl, sulfo-oxo, or thiol, as described herein.A “lower alkyl” group is an alkyl group containing from one to six(e.g., from one to four) carbon atoms.

Throughout the specification “alkyl” is generally used to refer to bothunsubstituted alkyl groups and substituted alkyl groups; however,substituted alkyl groups are also specifically referred to herein byidentifying the specific substituent(s) on the alkyl group. For example,the term “halogenated alkyl” or “haloalkyl” specifically refers to analkyl group that is substituted with one or more halide, e.g., fluorine,chlorine, bromine, or iodine. The term “alkoxyalkyl” specifically refersto an alkyl group that is substituted with one or more alkoxy groups, asdescribed below. The term “alkylamino” specifically refers to an alkylgroup that is substituted with one or more amino groups, as describedbelow, and the like. When “alkyl” is used in one instance and a specificterm such as “alkylalcohol” is used in another, it is not meant to implythat the term “alkyl” does not also refer to specific terms such as“alkylalcohol” and the like.

This practice is also used for other groups described herein. That is,while a term such as “cycloalkyl” refers to both unsubstituted andsubstituted cycloalkyl moieties, the substituted moieties can, inaddition, be specifically identified herein; for example, a particularsubstituted cycloalkyl can be referred to as, e.g., an“alkylcycloalkyl.” Similarly, a substituted alkoxy can be specificallyreferred to as, e.g., a “halogenated alkoxy,” a particular substitutedalkenyl can be, e.g., an “alkenylalcohol,” and the like. Again, thepractice of using a general term, such as “cycloalkyl,” and a specificterm, such as “alkylcycloalkyl,” is not meant to imply that the generalterm does not also include the specific term.

The term “cycloalkyl” as used herein is a non-aromatic carbon-based ringcomposed of at least three carbon atoms. Examples of cycloalkyl groupsinclude, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, norbornyl, and the like. The term “heterocycloalkyl” is atype of cycloalkyl group as defined above, and is included within themeaning of the term “cycloalkyl,” where at least one of the carbon atomsof the ring is replaced with a heteroatom such as, but not limited to,nitrogen, oxygen, sulfur, or phosphorus. The cycloalkyl group andheterocycloalkyl group can be substituted or unsubstituted. Thecycloalkyl group and heterocycloalkyl group can be substituted with oneor more groups including, but not limited to, alkyl, cycloalkyl, alkoxy,amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, or thiol asdescribed herein.

The term “polyalkylene group” as used herein is a group having two ormore CH₂ groups linked to one another. The polyalkylene group can berepresented by the formula —(CH₂)_(a)—, where “a” is an integer of from2 to 500.

The terms “alkoxy” and “alkoxyl” as used herein to refer to an alkyl orcycloalkyl group bonded through an ether linkage; that is, an “alkoxy”group can be defined as —OA¹ where A¹ is alkyl or cycloalkyl as definedabove. “Alkoxy” also includes polymers of alkoxy groups as justdescribed; that is, an alkoxy can be a polyether such as —OA¹-OA² or—OA¹-(OA²)_(a)-OA³, where “a” is an integer of from 1 to 200 and A¹, A²,and A³ are alkyl and/or cycloalkyl groups.

The term “alkenyl” as used herein is a hydrocarbon group of from 2 to 24carbon atoms with a structural formula containing at least onecarbon-carbon double bond. Asymmetric structures such as (A¹A²)C═C(A³A⁴) are intended to include both the E and Z isomers. This can bepresumed in structural formulae herein wherein an asymmetric alkene ispresent, or it can be explicitly indicated by the bond symbol C═C. Thealkenyl group can be substituted with one or more groups including, butnot limited to, alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl,alkynyl, cycloalkynyl, aryl, heteroaryl, aldehyde, amino, carboxylicacid, ester, ether, halide, hydroxy, ketone, azide, nitro, silyl,sulfo-oxo, or thiol, as described herein.

The term “cycloalkenyl” as used herein is a non-aromatic carbon-basedring composed of at least three carbon atoms and containing at least onecarbon-carbon double bond, i.e., C═C. Examples of cycloalkenyl groupsinclude, but are not limited to, cyclopropenyl, cyclobutenyl,cyclopentenyl, cyclopentadienyl, cyclohexenyl, cyclohexadienyl,norbornenyl, and the like. The term “heterocycloalkenyl” is a type ofcycloalkenyl group as defined above, and is included within the meaningof the term “cycloalkenyl,” where at least one of the carbon atoms ofthe ring is replaced with a heteroatom such as, but not limited to,nitrogen, oxygen, sulfur, or phosphorus. The cycloalkenyl group andheterocycloalkenyl group can be substituted or unsubstituted. Thecycloalkenyl group and heterocycloalkenyl group can be substituted withone or more groups including, but not limited to, alkyl, cycloalkyl,alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, heteroaryl,aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone,azide, nitro, silyl, sulfo-oxo, or thiol as described herein.

The term “alkynyl” as used herein is a hydrocarbon group of 2 to 24carbon atoms with a structural formula containing at least onecarbon-carbon triple bond. The alkynyl group can be unsubstituted orsubstituted with one or more groups including, but not limited to,alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl,aryl, heteroaryl, aldehyde, amino, carboxylic acid, ester, ether,halide, hydroxy, ketone, azide, nitro, silyl, sulfo-oxo, or thiol, asdescribed herein.

The term “cycloalkynyl” as used herein is a non-aromatic carbon-basedring composed of at least seven carbon atoms and containing at least onecarbon-carbon triple bound. Examples of cycloalkynyl groups include, butare not limited to, cycloheptynyl, cyclooctynyl, cyclononynyl, and thelike. The term “heterocycloalkynyl” is a type of cycloalkenyl group asdefined above, and is included within the meaning of the term“cycloalkynyl,” where at least one of the carbon atoms of the ring isreplaced with a heteroatom such as, but not limited to, nitrogen,oxygen, sulfur, or phosphorus. The cycloalkynyl group andheterocycloalkynyl group can be substituted or unsubstituted. Thecycloalkynyl group and heterocycloalkynyl group can be substituted withone or more groups including, but not limited to, alkyl, cycloalkyl,alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, heteroaryl,aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone,azide, nitro, silyl, sulfo-oxo, or thiol as described herein.

The term “aryl” as used herein is a group that contains any carbon-basedaromatic group including, but not limited to, benzene, naphthalene,phenyl, biphenyl, phenoxybenzene, and the like. The term “aryl” alsoincludes “heteroaryl,” which is defined as a group that contains anaromatic group that has at least one heteroatom incorporated within thering of the aromatic group. Examples of heteroatoms include, but are notlimited to, nitrogen, oxygen, sulfur, and phosphorus. Likewise, the term“non-heteroaryl,” which is also included in the term “aryl,” defines agroup that contains an aromatic group that does not contain aheteroatom. The aryl group can be substituted or unsubstituted. The arylgroup can be substituted with one or more groups including, but notlimited to, alkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl,cycloalkynyl, aryl, heteroaryl, aldehyde, amino, carboxylic acid, ester,ether, halide, hydroxy, ketone, azide, nitro, silyl, sulfo-oxo, or thiolas described herein. The term “biaryl” is a specific type of aryl groupand is included in the definition of “aryl.” Biaryl refers to two arylgroups that are bound together via a fused ring structure, as innaphthalene, or are attached via one or more carbon-carbon bonds, as inbiphenyl.

The term “aldehyde” as used herein is represented by the formula —C(O)H.Throughout this specification “C(O)” is a short hand notation for acarbonyl group, i.e., C═O.

The terms “amine” or “amino” as used herein are represented by theformula —NA¹A², where A¹ and A² can be, independently, hydrogen oralkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl,or heteroaryl group as described herein.

The term “alkylamino” as used herein is represented by the formula—NH(-alkyl) where alkyl is a described herein. Representative examplesinclude, but are not limited to, methylamino group, ethylamino group,propylamino group, isopropylamino group, butylamino group, isobutylaminogroup, (sec-butyl)amino group, (tert-butyl)amino group, pentylaminogroup, isopentylamino group, (tert-pentyl)amino group, hexylamino group,and the like.

The term “dialkylamino” as used herein is represented by the formula—N(-alkyl)₂ where alkyl is a described herein. Representative examplesinclude, but are not limited to, dimethylamino group, diethylaminogroup, dipropylamino group, diisopropylamino group, dibutylamino group,diisobutylamino group, di(sec-butyl)amino group, di(tert-butyl)aminogroup, dipentylamino group, diisopentylamino group, di(tert-pentyl)aminogroup, dihexylamino group, N-ethyl-N-methylamino group,N-methyl-N-propylamino group, N-ethyl-N-propylamino group and the like.

The term “carboxylic acid” as used herein is represented by the formula—C(O)OH.

The term “ester” as used herein is represented by the formula —OC(O)A¹or —C(O)OA¹, where A¹ can be alkyl, cycloalkyl, alkenyl, cycloalkenyl,alkynyl, cycloalkynyl, aryl, or heteroaryl group as described herein.The term “polyester” as used herein is represented by the formula-(A¹O(O)C-A²-C(O)O), or -(A¹O(O)C-A²-OC(O))_(a)—, where A¹ and A² canbe, independently, an alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl,cycloalkynyl, aryl, or heteroaryl group described herein and “a” is aninteger from 1 to 500. “Polyester” is as the term used to describe agroup that is produced by the reaction between a compound having atleast two carboxylic acid groups with a compound having at least twohydroxyl groups.

The term “ether” as used herein is represented by the formula A¹OA²,where A¹ and A² can be, independently, an alkyl, cycloalkyl, alkenyl,cycloalkenyl, alkynyl, cycloalkynyl, aryl, or heteroaryl group describedherein. The term “polyether” as used herein is represented by theformula -(A¹O-A²O)_(a)—, where A¹ and A² can be, independently, analkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl,or heteroaryl group described herein and “a” is an integer of from 1 to500. Examples of polyether groups include polyethylene oxide,polypropylene oxide, and polybutylene oxide.

The term “halide” as used herein refers to the halogens fluorine,chlorine, bromine, and iodine.

The term “heterocyclyl,” as used herein refers to single andmulti-cyclic non-aromatic ring systems and “heteroaryl” as used hereinrefers to single and multi-cyclic aromatic ring systems: in which atleast one of the ring members is other than carbon. The term“heterocyclyl” includes azetidine, dioxane, furan, imidazole,isothiazole, isoxazole, morpholine, oxazole, oxazole, including,1,2,3-oxadiazole, 1,2,5-oxadiazole and 1,3,4-oxadiazole, piperazine,piperidine, pyrazine, pyrazole, pyridazine, pyridine, pyrimidine,pyrrole, pyrrolidine, tetrahydrofuran, tetrahydropyran, tetrazine,including 1,2,4,5-tetrazine, tetrazole, including 1,2,3,4-tetrazole and1,2,4,5-tetrazole, thiadiazole, including, 1,2,3-thiadiazole,1,2,5-thiadiazole, and 1,3,4-thiadiazole, thiazole, thiophene, triazine,including 1,3,5-triazine and 1,2,4-triazine, triazole, including,1,2,3-triazole, 1,3,4-triazole, and the like.

The term “hydroxyl” as used herein is represented by the formula —OH.

The term “ketone” as used herein is represented by the formula A¹C(O)A²,where A¹ and A² can be, independently, an alkyl, cycloalkyl, alkenyl,cycloalkenyl, alkynyl, cycloalkynyl, aryl, or heteroaryl group asdescribed herein.

The term “azide” as used herein is represented by the formula —N₃.

The term “nitro” as used herein is represented by the formula —NO₂.

The term “nitrile” as used herein is represented by the formula —CN.

The term “ureido” as used herein refers to a urea group of the formula—NHC(O)NH₂ or —NHC(O)NH—.

The term “phosphoramide” as used herein refers to a group of the formula—P(O)(NA¹A²)₂, where A¹ and A² can be, independently, hydrogen or analkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl,aryl, or heteroaryl group as described herein.

The term “carbamoyl” as used herein refers to an amide group of theformula —CONA¹A², where A¹ and A² can be, independently, hydrogen or analkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl,aryl, or heteroaryl group as described herein.

The term “sulfamoyl” as used herein refers to a group of the formula—S(O)₂NA¹A², where A¹ and A² can be, independently, hydrogen or analkyl, cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl,aryl, or heteroaryl group as described herein.

The term “silyl” as used herein is represented by the formula —SiA¹A²A³,where A¹, A², and A³ can be, independently, hydrogen or an alkyl,cycloalkyl, alkoxy, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl,or heteroaryl group as described herein.

The term “sulfo-oxo” as used herein is represented by the formulas—S(O)A¹, —S(O)₂A¹, —OS(O)₂A′, or —OS(O)₂OA¹, where A¹ is hydrogen or analkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl,or heteroaryl group as described herein. Throughout this specification“S(O)” is a short hand notation for S═O. The term “sulfonyl” is usedherein to refer to the sulfo-oxo group represented by the formula—S(O)₂A′, where A¹ is hydrogen or an alkyl, cycloalkyl, alkenyl,cycloalkenyl, alkynyl, cycloalkynyl, aryl, or heteroaryl group asdescribed herein. The term “sulfone” as used herein is represented bythe formula A¹S(O)₂A², where A¹ and A² can be, independently, an alkyl,cycloalkyl, alkenyl, cycloalkenyl, alkynyl, cycloalkynyl, aryl, orheteroaryl group as described herein. The term “sulfoxide” as usedherein is represented by the formula A'S(O)A², where A¹ and A² can be,independently, an alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl,cycloalkynyl, aryl, or heteroaryl group as described herein.

The term “thiol” as used herein is represented by the formula —SH.

“R,” “R¹,” “R²,” “R³,” “R^(n),” where n is an integer, as used hereincan, independently, include hydrogen or one or more of the groups listedabove. For example, if R¹ is a straight chain alkyl group, one of thehydrogen atoms of the alkyl group can optionally be substituted with ahydroxyl group, an alkoxy group, an alkyl group, a halide, and the like.Depending upon the groups that are selected, a first group can beincorporated within a second group or, alternatively, the first groupcan be pendant (i.e., attached) to the second group. For example, withthe phrase “an alkyl group comprising an amino group,” the amino groupcan be incorporated within the backbone of the alkyl group.Alternatively, the amino group can be attached to the backbone of thealkyl group. The nature of the group(s) that is (are) selected willdetermine if the first group is embedded or attached to the secondgroup.

As described herein, compounds of the disclosure may contain “optionallysubstituted” moieties. In general, the term “substituted,” whetherpreceded by the term “optionally” or not, means that one or morehydrogens of the designated moiety are replaced with a suitablesubstituent. Unless otherwise indicated, an “optionally substituted”group may have a suitable substituent at each substitutable position ofthe group, and when more than one position in any given structure may besubstituted with more than one substituent selected from a specifiedgroup, the substituent may be either the same or different at everyposition. Combinations of substituents envisioned by this disclosure arepreferably those that result in the formation of stable or chemicallyfeasible compounds. It is also contemplated that, in certain aspects,unless expressly indicated to the contrary, individual substituents canbe further optionally substituted (i.e., further substituted orunsubstituted).

In some aspects, a structure of a compound can be represented by aformula:

which is understood to be equivalent to a formula:

wherein n is typically an integer. That is, R is understood to representfive independent substituents, R^(n(a)), R^(n(b)), R^(n(c)), R^(n(d)),R^(n(e)). By “independent substituents,” it is meant that each Rsubstituent can be independently defined. For example, if in oneinstance R^(n(a)) is halogen, then R^(n(b)) is not necessarily halogenin that instance.

Several references to R, R¹, R², R³, R⁴, R⁵, R⁶, etc. are made inchemical structures and moieties disclosed and described herein. Anydescription of R, R¹, R², R³, R⁴, R⁵, R⁶, etc. in the specification isapplicable to any structure or moiety reciting R, R¹, R², R³, R⁴, R⁵,R⁶, etc. respectively.

Phosphorescent/MADF emitters may b used for efficient exciton harvestingwhile emitting primarily from horizontally aligned and stablefluorescent emitters in order to enhance the device efficiency anddevice operational lifetime. To achieve this, both phosphorescent/MADFemitters and fluorescent emitters must be present in the EML and energytransfer between the MADF and fluorescent materials is necessary. Twomajor mechanisms to exciton transport exist, namely the Dexter energytransfer and Forster resonant energy transfer (FRET) mechanisms. Theformer is a short range transport which consists of consecutive hoppingof excitons between neighboring molecules which depends on the orbitaloverlap between the molecules. The latter is a long range transportprocess in which dipole coupling between an excited donor molecule (D)and a ground state acceptor molecule (A) leads to a long rangenon-radiative transfer. This process depends on the overlap between theemission profile of D and the absorption of A. This transfer mechanismnecessitates and allowed relaxation transition of the donor molecule andan allowed excitation mechanism of the acceptor molecules, thus, FRETtypically occurs between singlet excitons. However, if thephosphorescent emission process of the donor molecule is efficient,transfer between the triplet of the donor molecule and the singlet ofthe acceptor molecule is also possible.

The stability and efficiency of blue phosphorescent OLEDs has remainedas a great technical challenge for OLED displays and lightingapplications. Thus, alternate solution will be to improve the deviceefficiency of blue fluorescent OLED with better device stability. Asillustrated in FIG. 2 and FIG. 3, a process can be envisioned in whichall the excitons are formed on a phosphorescent/MADF donor materialwhich can then transfer via FRET to a fluorescent acceptor material andemit with high efficiency. Such a process would maintain the 100%utilization of electrogenerated excitons while emitting primarily fromthe fluorescent emitter to achieve high stability and avoidtriplet-triplet annihilation. Moreover, horizontally orientedfluorescent emitters will enable a potentially high outcouplingefficiency and improve the device efficiency. As an added benefit, thecolor quality of EL spectra of devices will also improve if the emissionoriginated solely from the narrow band fluorescent emitters.

This can be achieved by harvesting the electrogenerated excitons with aphosphorescent material then transferring the energy to a fluorescentemitter through a FRET mechanism. There are at least two methods ofcreating such a system: 1) a single emissive layer containing both thephosphorescent/MADF emitter and the fluorescent emitter doped into ahost matrix and 2) an emissive layer containing alternating fluorescentand phosphorescent/MADF doped layers, which are presented in FIG. 4 andFIG. 5, respectively. In either case some constraints in the materialsselection exist. Firstly, the emission spectrum of thephosphorescent/MADF donor should be selected to have significantspectral overlap with the absorption spectrum of the fluorescent emitterin order for the FRET process to occur. Additionally, thephotoluminescent quantum yield of the phosphorescent/MADF materialshould be high enough to ensure that the dipole relaxation in the FRETprocess can occur with high efficiency. Similarly, the photoluminescentquantum yield of the fluorescent emitter should be high enough to ensureefficient emission. Thirdly, the fluorescent emitters will havepreferred horizontally oriented emitting dipoles inside of the emissivelayer.

The first case, FIG. 4, is composed of an OLED device which contains anemissive layer which is composed of a mixed layer of aphosphorescent/MADF donor material and a fluorescent emitter dispersedwithin a host matrix. In such a case where both the phosphorescent/MADFand fluorescent materials exist within the same layer, care must betaken to avoid direct formation of excitons on the fluorescent emitter(which can only harvest singlet excitons) to ensure that 100% of theelectrogenerated excitons are utilized. On the other hand, theconcentration of the fluorescent emitter must be high enough for thereto close proximity between the phosphorescent/MADF material and thefluorescent emitter so that rapid transfer from the MADF donor to thefluorescent emitter can be achieved and direct triplet emission ortriplet-triplet annihilation can be avoided.

The second case, FIG. 5, is composed of an OLED device which contains anemissive layer with alternating fluorescent and phosphorescent/MADFdoped layers. In such a case the thickness and location of the layersmust be tuned to ensure that exciton formation primarily occurs in theregion which is doped with the phosphorescent/MADF material.Furthermore, the region which contains the fluorescent doped layershould be close enough to the exciton formation zone so that thefluorescent emitters are within the distance for FRET to occur.

A typical EQE of OLEDs on a standard glass substrate is limited to20-30% if the emitting dipoles or emitters are randomly oriented (FIG.6A). However, the device EQE could be improved to 45% (FIG. 6C) if thereare 100% horizontally oriented emitting dipoles in the emissive layer(FIG. 6B), which simultaneously suppress the plasmonic quenching processand enhance ratio of photons trapped in the substrate, capable of beingextracted by microlens or macroextractors for illumination purpose.

Compounds

Owing to the potential of phosphorescent tetradentate platinum complexesfor harvesting both electro-generated singlet and triplet excitons toachieve 100% internal quantum efficiency, these complexes are goodcandidates for the emitting materials of OLEDs. In some embodiments,there is an “emitting portion” and an “ancillary portion” in a ligand ofplatinum complex (e.g., a tetradentate platinum complex). If stabilizingsubstitution(s), such as conjugated group(s), aryl or heteroaromaticsubstitution(s) and so on, were introduced into the emitting portion,the “Highest Occupied Molecular Orbital” (HOMO) energy level, the“Lowest Unoccupied Molecular Orbital” (LUMO) energy level, or both maybe changed. Accordingly, in some embodiments the energy gap between theHOMO and LUMO can be tuned. Thus, the emission spectra of phosphorescenttetradentate platinum complexes can be modified to lesser or greaterextents, such that the emission spectra can become narrower or broader,such that the emission spectra can exhibit a blue shift or a red shift,or a combination thereof.

The emission of the disclosed complexes can be tuned, for example, fromthe ultraviolet to near-infrared, by, for example, modifying the ligandstructure. In another aspect, the disclosed complexes can provideemission over a majority of the visible spectrum. In one embodiment, thedisclosed complexes can emit light over a range of from about 400 nm toabout 700 nm. In another aspect, the disclosed complexes have improvedstability and efficiency over traditional emission complexes. In yetanother aspect, the disclosed complexes can be useful as luminescentlabels in, for example, bio-applications, anti-cancer agents, emittersin organic light emitting devices (OLED), or a combination thereof. Inanother aspect, the disclosed complexes can be useful in light emittingdevices, such as, for example, compact fluorescent lamps (CFL), lightemitting diodes (LED), incandescent lamps, and combinations thereof.

The compounds can also have other known emission mechanisms which areuseful in devices.

Disclosed herein are compounds or compound complexes comprising platinumand/or palladium. The terms compound, complex, or combinations thereof,are used interchangeably herein. In one aspect, the compounds disclosedherein have a neutral charge.

The compounds disclosed herein can exhibit desirable properties and haveemission spectra, absorption spectra, or both that can be tuned via theselection of appropriate ligands. In another aspect, the presentdisclosure can exclude any one or more of the compounds, structures, orportions thereof, specifically recited herein.

The compounds disclosed herein are suited for use in a wide variety ofoptical and electro-optical devices, including, but not limited to,photo-absorbing devices such as solar- and photo-sensitive devices,organic light emitting devices (OLEDs), photo-emitting devices, ordevices capable of both photo-absorption and emission and as markers forbio-applications.

As briefly described above, the disclosed compounds are platinum and/orpalladium complexes. In one aspect, the compounds disclosed herein canbe used as host materials for OLED applications, such as full colordisplays.

The compounds disclosed herein are useful in a variety of applications.As light emitting materials, the compounds can be useful in organiclight emitting devices (OLEDs), luminescent devices and displays, andother light emitting devices.

In another aspect, the compounds can provide improved efficiency,improved operational lifetimes, or both in lighting devices, such as,for example, organic light emitting devices, as compared to conventionalmaterials.

The compounds of the disclosure can be made using a variety of methods,including, but not limited to those recited in the examples providedherein.

Compounds

In one aspect, the present disclosure relates to compounds having theformula

wherein M is a metal cation with two positive charges selected from Pt(II) or Pd (II);

wherein E¹, E², and E³ independently is a linking group comprising O,NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene, or R² and R³ together form C═O, wherein eachof R² and R³ independently is optionally linked to a C or N, therebyforming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with three positive charges selected from Au(III) or Ag (III);

wherein E¹, E², and E³ independently is a linking group comprising O,NR², CR²R³, S. AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, arylalkene, or R² and R³ together form C═O, wherein each ofR² and R³ independently is optionally linked to a C or N, therebyforming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein N is selected from a substituted or unsubstituted heterocyclicgroup wherein a nitrogen atom coordinated to the metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with one positive charges selected from Ir(I) or Rh (I),

wherein E¹, E², and E³ independently represent a linking groupcomprising O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to a C orN, thereby forming a cyclic structure;

wherein C is selected from a substituted or unsubstituted aromatic ringor heterocyclic group, wherein a carbon atom is coordinated to themetal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group wherein a nitrogen atom is coordinatedto the metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with three positive charges selected from Ir(III), Rh (III), Co (III), Al (III), or Ga (III),

wherein E¹, E², E³, and E⁴ independently is a linking group comprisingO, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, arylalkene, or R² and R³ together form C═O, wherein each ofR² and R³ independently is optionally linked to a C or N, therebyforming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with three positive charges selected from Ir(III), Rh (III), Co (III), Al (III), or Ga (III);

wherein E¹, E², E³, E⁴, and E⁵ independently is a linking groupcomprising O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to a C orN, thereby forming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with four positive charges selected from Pd(IV) and Pt (IV);

wherein E¹, E², E³, and E⁴ independently is a linking group comprisingO, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, arylalkene, or R² and R³ together form C═O, wherein each ofR² and R³ independently is optionally linked to a C or N, therebyforming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

where M is a metal cation with four positive charges selected from Pd(IV) and Pt(IV),

wherein E¹, E², E³, E⁴, and E⁵ independently is a linking groupcomprising O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to a C orN, thereby forming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with two positive charges selected from Ru(II), or Os (II);

wherein E¹, E², E³, E⁴, and E⁵ independently is a linking groupcomprising O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to a C orN, thereby forming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom coordinated tothe metal.

In another aspect, the present disclosure relates to compounds havingthe formula

wherein M is a metal cation with two positive charges selected from Ru(II), or Os (II);

wherein E¹, E², E³, and E⁴ independently is a linking group comprisingO, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen, alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, arylalkene, or R² and R³ together form C═O, wherein each ofR² and R³ independently is optionally linked to a C or N, therebyforming a cyclic structure;

wherein each C independently is selected from a substituted orunsubstituted aromatic ring or heterocyclic group, wherein a carbon atomis coordinated to the metal; and

wherein each N independently is selected from a substituted orunsubstituted heterocyclic group, wherein a nitrogen atom is coordinatedto the metal.

In one aspect, the present disclosure relates to compounds having thestructure of Formula I or Formula II:

wherein A is an accepting group comprising one or more of the followingstructures, which can optionally be substituted:

wherein D is a donor group comprising of one or more of the followingstructures, which can optionally be substituted:

wherein C in Formula I or Formula II comprises one or more of thefollowing structures, which can optionally be substituted:

wherein N in Formula I or II comprises one or more of the followingstructures, which can optionally be substituted:

wherein each of a⁰, a¹, and a² independently is present or absent, andif present, comprises a direct bond and/or linking group comprising oneor more of the following:

wherein each occurrence of a is independently substituted orunsubstituted N or substituted or unsubstituted C; wherein b¹ and b²independently is present or absent, and if present, comprises a linkinggroup comprising one or more of the following:

-   -   wherein each occurrence of X is independently B, C, N, O, Si, P,        S, Ge, As, Se, Sn, Sb, or Te;    -   wherein Y is O, S, S═O, SO₂, Se, N, NR³, PR³, RP═O, CR¹R², C═O,        SiR¹R², GeR¹R², BH, P(O)H, PH, NH, CR¹H, CH₂, SiH₂, SiHR¹. BH,        or BR³, wherein each of R, R¹, R², and R³ independently is        hydrogen, aryl, cycloalkyl, cycloalkenyl, heterocyclyl,        heteroaryl, alkyl, alkenyl, alkynyl, deuterium, halogen,        hydroxyl, thiol, nitro, cyano, amino, a mono- or di-alkylamino,        a mono- or diaryl amino, alkoxy, aryloxy, haloalkyl, aralkyl,        ester, nitrile, isonitrile, alkoxycarbonyl, acylamino,        alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino,        sulfamoyl, carbamoyl, alkylthio, sulfinyl, ureido,        phosphoramide, mercapto, sulfo, carboxyl, hydrazino, substituted        silyl, or polymerizable, or any conjugate or combination        thereof, wherein n is a number that satisfies the valency of Y,        and wherein M is platinum (II), palladium (II), nickel (II),        manganese (II), zinc (II), gold (III), silver (III), copper        (III), iridium (I), rhodium (I), and/or cobalt (I).

In one embodiment, a² is absent in Formula I. In one embodiment, a² andb² are absent in Formula I or Formula II.

In one embodiment, X is N.

In one embodiment, A is

a² is absent, b² are absent, and D is

In one embodiment, C in Formula I or Formula II is

In one embodiment, N in Formula I or Formula II is substituted orunsubstituted

In one embodiment, the compound having Formula I or Formula II is acompound having Formula III;

wherein M is Ir, Rh, Mn, Ni, Cu, or Ag;

wherein each of R¹ and R² independently are hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene;

wherein each of Y^(1a) and Y^(1b) independently is O, NR², CR²R³, S,AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof, whereineach of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure;

wherein each of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N orCR^(6a), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

each of Y^(3a), Y^(3b), Y^(3c), Y^(3d), Y^(4a), Y^(4b), Y^(4c), andY^(4d) independently is N, O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂,wherein each of R^(6a) and R^(6b) is independently hydrogen, substitutedor unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein Z is C or Si, and whereineach R^(6c) independently is hydrogen, substituted or unsubstitutedalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of m and n independently is an integer of 1 or 2; and

wherein each of

independently is partial or full unsaturation of the ring with which itis associated.

In one embodiment, Y^(2b) is C; Y^(2c), Y^(3b) and Y^(4b) are N. In oneembodiment, M is Ir or Rh.

In one embodiment, the compound having Formula I or Formula II is acompound having Formula IV;

wherein M is Pt, Pd and Au;

wherein each of R¹ and R² independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene;

wherein each of Y^(1a) a and Y^(1b) independently is O, NR², CR²R³, S,AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof, whereineach of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure;

wherein each of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N orCR^(6b), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of Y^(3a), Y^(3b), Y^(3c), Y^(3d), Y^(3e), Y^(3f), Y^(4a),Y^(4b), Y^(4c), and Y^(4d) independently is N, O, S, NR^(6a), CR^(6b),or Z(R^(6c))₂, wherein each of R^(6a) and R^(6b) is independentlyhydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene; wherein Zis C or Si, and wherein each R^(6c) independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, or arylalkene;

wherein each of m is an integer of 1 or 2; and

wherein each of

independently is partial or full unsaturation of the ring with which itis associated.

In one embodiment, Y^(2b) and Y^(2c) is C. In one embodiment, Y^(3b) andY^(4b) is N. In one embodiment, each of Y^(1a) and Y^(1b) independentlyis O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof. In one embodiment, each of R² and R³ independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³ together formC═O. In one embodiment, each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure. In one embodiment, M is Pt or Pd.

In one embodiment, Y^(2b), Y^(2c) and Y^(4b) is C. In one embodiment,Y^(3b) is N. In one embodiment, each of Y^(1a) and Y^(1b) independentlyis O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof. In one embodiment, each of R² and R³ independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R¹ together formC═O. In one embodiment, each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure. In one embodiment, M is Au.

In one embodiment, the compound having Formula I or Formula II is acompound having Formula V;

wherein M is Pt, Pd, Au, Ag;

wherein each of R¹ and R² independently are hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene;

wherein one of Y^(1a) and Y^(1b) is B(R²)₂ and the other of Y^(1a) andY^(1b) is O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³together form C═O, wherein each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure;

wherein each of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N orCR^(6a), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of Y^(3a), Y^(3b), Y^(3c), Y^(3d), Y^(4a), Y^(4b), Y^(4c),and Y^(4d) independently is N, O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂,wherein each of R^(6a) and R^(6b) is independently hydrogen, substitutedor unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein Z is C or Si, and whereineach R^(6c) independently is hydrogen, substituted or unsubstitutedalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of m and n independently are an integer 1 or 2;

wherein each of

independently is partial or full unsaturation of the ring with which itis associated.

In one embodiment, the compound having Formula I or Formula II is acompound having Formula VI or Formula VIb

wherein M is Pt, Pd, Ir, Rh, or Au;

wherein each of R¹ and R² independently are hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein each of Y^(1a), Y^(1b),and Y^(1c) independently is O, NR², CR²R³, S, AsR², BR², PR², P(O)R², orSiR²R³, or a combination thereof, wherein each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene, or R² and R³ together form C═O, wherein each of R² and R³independently is optionally linked to an adjacent ring structure,thereby forming a cyclic structure;

wherein each of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N,NR^(6a), or CR^(6b), wherein each of R^(6a) and R^(6b) independently ishydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene;

each of Y^(3a), Y^(3b), Y^(3c), Y^(3d), Y^(3e), Y^(4a), Y^(4b), Y^(4c),and Y^(4d) independently is N, O, S, NR^(6a), CR^(6b), or Z(R)₂, whereineach of R^(6a) and R^(6b) is independently hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein Z is C or Si, and whereineach R^(6c) independently is hydrogen, substituted or unsubstitutedalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of m and n independently are an integer 1 or 2;

wherein each of

independently is partial or full unsaturation of the ring with which itis associated.

In one embodiment, each of R² and R³ independently is linked to anadjacent ring structure.

In one embodiment, m is 2. In one embodiment, n is 2. In one embodiment,Y^(2b) and Y^(2c) are CH. In one embodiment, Y^(3b) and Y^(4b) are N. Inone embodiment, at least one of Y^(1b) and Y^(1c) is NR², CR²R³, AsR²,BR², PR², P(O)R², or SiR²R³, or a combination thereof. In oneembodiment, each of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O. Inone embodiment, each of R² and R³ independently is optionally linked toan adjacent ring structure, thereby forming a cyclic structure. In oneembodiment, M is Pt or Pd.

In one embodiment, at least of one of Y^(2a), Y^(2d), Y^(3d) and Y^(4d)is C. In one embodiment, at least one of Y^(1b) and Y^(1c) is NR²,CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof. Inone embodiment, each of R² and R³ independently is hydrogen, substitutedor unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene. In one embodiment, R² is covalentlylinked to at least one of Y^(2a), Y^(2d), Y^(3d) and Y^(4d), therebyforming a cyclic structure. In one embodiment, M is Pt or Pd.

In one embodiment, m is 2. In one embodiment, n is 2. In one embodiment,Y^(2b) is CH. In one embodiment, Y^(3b), Y^(2c) and Y^(4b) are N. In oneembodiment, Y^(1b) is NR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, ora combination thereof. In one embodiment, each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene, or R² and R³ together form C═O. In one embodiment, each ofR² and R³ independently is optionally linked to an adjacent ringstructure, thereby forming a cyclic structure. In one embodiment, M isIr or Rh.

In one embodiment, at least of one of Y^(2a) and Y^(3d) is C. In oneembodiment, Y^(1b) is NR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, ora combination thereof. In one embodiment, each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene. In one embodiment, R² is covalently linked to at least oneof Y^(2a) and Y^(3d), thereby forming a cyclic structure. In oneembodiment, M is Ir or Rh.

In one embodiment, m is 2. In one embodiment, n is 2. In one embodiment,Y^(2b), Y^(2c) and Y^(4b) are CH. In one embodiment, Y^(3b) is N. In oneembodiment, Y^(1b) is NR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, ora combination thereof. In one embodiment, each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene, or R² and R³ together form C═O. In one embodiment, each ofR² and R³ independently is optionally linked to an adjacent ringstructure, thereby forming a cyclic structure. In one embodiment, M isAu.

In one embodiment, at least of one of Y^(2a) and Y^(3d) is C. In oneembodiment, Y^(1b) is NR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, ora combination thereof. In one embodiment, each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene. In one embodiment, R² is covalently linked to at least oneof Y^(2a) and Y^(3d), thereby forming a cyclic structure. In oneembodiment, M is Au.

In one embodiment, the compound having Formula I or Formula II is acompound having Formula VII;

wherein M comprises Ir, Rh, Pt, Os, Zr, Co or Ru;

wherein each of R¹ and R² independently are hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene;

wherein each of Y^(1a), Y^(1c) and Y^(1d) independently is O, NR²,CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof,wherein each of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure;

wherein Y^(1c) is present or not present; wherein when Y^(1e) ispresent, Y^(1e) represents O, NR², CR²R³, S, AsR², BR², PR², P(O)R², orSiR²R³, or a combination thereof; wherein each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene, or R² and R³ together form C═O, wherein each of R² and R³independently is optionally linked to an adjacent ring structure,thereby forming a cyclic structure; wherein when Y^(1e) is not present,Y^(1e) represents no bond;

wherein each of Y^(2a), Y^(2b) Y^(2c), and Y^(2d) independently is N orCR^(6a), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene;

wherein each of Y^(3a), Y^(3b), Y^(3c), Y^(3d), Y^(3e), Y^(4a), Y^(4b),Y^(4c), and Y^(4d) independently is N, O, S, NR^(6a), CR^(6b), orZ(R^(6c))₂, wherein each of R^(6a) and R^(6b) is independently hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, or arylalkene; wherein Z is C or Si, andwherein each R^(6c) independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene;

wherein in each of each of Y^(5a), Y^(5b), Y^(5c), Y^(5d), Y^(6a),Y^(6b), Y^(6c), and Y^(6d) independently is N, O, S, NR^(6a), or CR;

wherein each of m, n, l and p independently is an integer of 1 or 2;

wherein each of

independently is partial or full unsaturation of the ring with which itis associated.

In one embodiment, in the compound of Formula VII, at least one of m, n,l, and p is 2; Y^(2b) and Y^(2c) are CH. In one embodiment, Y^(3b) andY^(4b) are N. In one embodiment, at least one of Y^(1b) and Y^(1c) isNR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof.In one embodiment, each of R² and R³ independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³ together formC═O. In one embodiment, each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure. In one embodiment, M is Ir or Rh.

In one embodiment, in the compound of Formula VII, at least of one ofY^(2a), Y^(2d), Y^(3d) and Y^(4d) is C. In one embodiment, at least oneof Y^(1c) and Y^(1d) is NR², CR²R³, AsR², BR², PR², P(O)R², or SiR²R³,or a combination thereof. In one embodiment, each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene. In one embodiment, R² is covalently linked to at least oneof Y^(2a), Y^(2d), Y^(3d) and Y^(4d), thereby forming a cyclicstructure. In one embodiment, M is Ir or Rh.

In one embodiment, in the compound of Formula VII, each of R² and R³independently is linked to an adjacent ring structure.

In one embodiment, the phosphorescent/MADF emitter is PtNON;

Exemplary fluorescent emitters include, but are not limited to:

1. Aromatic Hydrocarbons and their Derivatives

2. Arylethylene, Arylacetylene and their Derivatives

3. Heterocyclic Compounds and their Derivatives

4. Other Fluorescent Luminophors

wherein each of R¹¹, R²¹, R³¹, R⁴¹, R⁵¹, R⁶¹, R⁷¹ and R⁸¹ independentlyrepresents hydrogen, aryl, cycloalkyl, cycloalkenyl, heterocyclyl,heteroaryl, alkyl, alkenyl, alkynyl, deuterium, halogen, hydroxyl,thiol, nitro, cyano, amino, a mono- or di-alkylamino, a mono- ordiarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, nitrile,isonitrile, heteroaryl, alkoxycarbonyl, acylamino, alkoxycarbonylamino,aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio,sulfinyl, ureido, phosphoramide, mercapto, sulfo, carboxyl, hydrazino,substituted silyl, polymeric, or any conjugate or combination thereof.

wherein each of Y^(a), Y^(b), Y^(c), Y^(d), Y^(e), Y^(f), Y^(g), Y^(h),Y^(i), Y^(j), Y^(k), Y¹, Y^(m), Y^(n), Y^(o) and Y^(p) independentlyrepresents C, N or B; and

wherein each of U^(a), U^(b) and U^(c) independently represents CH₂,CR¹R², C═O, CH₂, SiR¹R², GeH₂, GeR¹R², NH, NR³, PH, PR³, R³P═O, AsR³,R³As═O, O, S, S═O, SO₂, Se, Se═O, SeO₂, BH, BR³, R³Bi═O, BiH, or BiR³;wherein each of R¹, R², and R³ independently are hydrogen, substitutedor unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene.

In one embodiment, the fluorescent emitter is a thermally active delayedfluorescent (TADF) emitter. Exemplary TADF emitters include, but are notlimited to, DABNA-1 and DABNA-2.

Hosts:

In one embodiment, the devices of the present disclosure may include ahost material In one embodiment, the host material comprises acarbazole-based host material. Suitable carbazole based host materialsinclude, but are not limited to, compounds having one to three carbazoleskeletons, such as compounds of Formulas 1-3:

In Formulas 1-3, each of R¹-R⁹ independently represents hydrogen,halogen, hydroxyl, nitro, cyanide, thiol, or optionally substitutedalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene.

Further non-limiting examples of suitable carbazole-based host materialsinclude (9,9′,9″-triphenyl-9H,9′H,9″H-3,3′:6′3″-tercarbazole)(tris-PCz), (4,4-di(9H-carbazol-9-yl) biphenyl) (CBP),(3,3-di(9H-carbazol-9-yl) biphenyl) (mCBP), meta-di(carbazolyl) phenyl(mCP) shown below.

Additional carbazole-based hosts include, but are not limited to, mCPy(2,6-bis(N-carbazolyl)pyridine), TCP (1,3,5-tris(carbazol-9-yl)benzene),TCTA (4,4′,4″-tris(carbazol-9-yl)triphenylamine), TPBi(1,3,5-tris(1-phenyl-1-H-benzimidazol-2-yl)benzene), pCBP(4,4′-bis(carbazol-9-yl)biphenyl), CDBP(4,4′-bis(9-carbazolyl)-2,2′-dimethylbiphenyl), DMFL-CBP(4,4′-bis(carbazol-9-yl)-9,9-dimethylfluorene), FL-4CBP(4,4′-bis(carbazol-9-yl)-9,9-bis(9-phenyl-9H-carbazole)fluorene),FL-2CBP (9,9-bis(4-carbazol-9-yl)phenyl)fluorene, also abbreviated asCPF), DPFL-CBP (4,4′-bis(carbazol-9-yl)-9,9-ditolylfluorene), FL-2CBP(9,9-bis(9-phenyl-9H-carbazole)fluorene), Spiro-CBP(2,2′,7,7′-tetrakis(carbazol-9-yl)-9,9′-spirobifluorene). In oneembodiment, a single host is used. In one embodiment, a mixture of twoor more hosts is used. In one embodiment, the mixture of hosts maycomprise between 0.01% and 99.99% of at least one host and between 0.01%and 99.99% of a second host.

Compositions and Devices

Also disclosed herein are devices comprising one or more compound and/orcompositions disclosed herein.

In one aspect, the device is an electro-optical device. Electro-opticaldevices include, but are not limited to, photo-absorbing devices such assolar- and photo-sensitive devices, organic light emitting devices(OLEDs), photo-emitting devices, or devices capable of bothphoto-absorption and emission and as markers for bio-applications. Forexample, the device can be an OLED.

OLEDs make use of thin organic films that emit light when voltage isapplied across the device. OLEDs are becoming an increasinglyinteresting technology for use in applications such as flat paneldisplays, illumination, and backlighting. Several OLED materials andconfigurations are described in U.S. Pat. Nos. 5,844,363, 6,303,238, and5,707,745, which are incorporated herein by reference in their entirety.

Generally, an OLED comprises at least one organic layer disposed betweenand electrically connected to an anode and a cathode. When a current isapplied, the anode injects holes and the cathode injects electrons intothe organic layer(s). The injected holes and electrons each migratetoward the oppositely charged electrode. When an electron and holelocalize on the same molecule, an “exciton,” which is a localizedelectron-hole pair having an excited energy state, is formed. Light isemitted when the exciton relaxes via a photoemissive mechanism. In somecases, the exciton may be localized on an excimer or an exciplex.Non-radiative mechanisms, such as thermal relaxation, may also occur,but are generally considered undesirable.

The initial OLEDs used emissive molecules that emitted light from theirsinglet states (“fluorescence”) as disclosed, for example, in U.S. Pat.No. 4,769,292, which is incorporated by reference in its entirety.Fluorescent emission generally occurs in a time frame of less than 10nanoseconds.

More recently, OLEDs having emissive materials that emit light fromtriplet states (“phosphorescence”) have been demonstrated. Baldo et al.,“Highly Efficient Phosphorescent Emission from OrganicElectroluminescent Devices,” Nature, vol. 395, 151-154, 1998;(“Baldo-I”) and Baldo et al., “Very high-efficiency green organiclight-emitting devices based on electrophosphorescence,” Appl. Phys.Lett., vol. 75, No. 3, 4-6 (1999) (“Baldo-II”), which are incorporatedby reference in their entireties. Phosphorescence is described in moredetail in U.S. Pat. No. 7,279,704 at cols. 5-6, which are incorporatedby reference.

One application for phosphorescent emissive molecules is a full colordisplay. Industry standards for such a display call for pixels adaptedto emit particular colors, referred to as “saturated” colors. Inparticular, these standards call for saturated red, green, and bluepixels. Color may be measured using CIE coordinates, which are wellknown to the art. Such devices are disclosed herein which comprise oneor more of the compounds or compositions disclosed herein.

OLEDs can be produced by methods known to those skilled in the art. Ingeneral, the OLED is produced by successive vapor deposition of theindividual layers onto a suitable substrate. Suitable substratesinclude, for example, glass, inorganic materials such as ITO or IZO orpolymer films. For the vapor deposition, customary techniques may beused, such as thermal evaporation, chemical vapor deposition (CVD),physical vapor deposition (PVD) and others.

In an alternative process, the organic layers may be coated fromsolutions or dispersions in suitable solvents, in which case coatingtechniques known to those skilled in the art are employed. Suitablecoating techniques are, for example, spin-coating, the casting method,the Langmuir-Blodgett (“LB”) method, the inkjet printing method,dip-coating, letterpress printing, screen printing, doctor bladeprinting, slit-coating, roller printing, reverse roller printing, offsetlithography printing, flexographic printing, web printing, spraycoating, coating by a brush or pad printing, and the like. Among theprocesses mentioned, in addition to the aforementioned vapor deposition,preference is given to spin-coating, the inkjet printing method and thecasting method since they are particularly simple and inexpensive toperform. In the case that layers of the OLED are obtained by thespin-coating method, the casting method or the inkjet printing method,the coating can be obtained using a solution prepared by dissolving thecomposition in a concentration of 0.0001 to 90% by weight in a suitableorganic solvent such as benzene, toluene, xylene, tetrahydrofuran,methyltetrahydrofuran, N,N-dimethylformamide, acetone, acetonitrile,anisole, dichloromethane, dimethyl sulfoxide, water and mixturesthereof.

According to one aspect of the present disclosure, an OLED is provided.The OLED includes an anode, a cathode, and at least one organic layerdisposed between the anode and the cathode. The at least one organiclayer may include a host and a phosphorescent dopant and/or afluorescent dopant The organic layer can include a compound of Formula Ior Formula II, and its variations as described herein.

FIG. 1 depicts a cross-sectional view of an exemplary OLED 100. OLED 100includes substrate 102, anode 104, hole-transporting material(s) (HTL)106, light processing material 108, electron-transporting material(s)(ETL) 110, and a metal cathode layer 112. Anode 104 is typically atransparent material, such as indium tin oxide. Light processingmaterial 108 may be an emissive material (EML) including an emitter anda host.

In various aspects, any of the one or more layers depicted in FIG. 1 mayinclude indium tin oxide (ITO), poly(3,4-ethylenedioxythiophene)(PEDOT), polystyrene sulfonate (PSS),N,N′-di-1-naphthyl-N,N-diphenyl-1,1′-biphenyl-4,4′ diamine (NPD),1,1-bis((di-4-tolylamino)phenyl)cyclohexane (TAPC),2,6-Bis(N-carbazolyl)pyridine (mCpy),2,8-bis(diphenylphosphoryl)dibenzothiophene (PO15), LiF, Al, or acombination thereof.

Light processing material 108 may include one or more compounds of thepresent disclosure optionally together with a host material. The hostmaterial can be any suitable host material known in the art. Theemission color of an OLED is determined by the emission energy (opticalenergy gap) of the light processing material 108, which can be tuned bytuning the electronic structure of the emitting compounds, the hostmaterial, or both. Both the hole-transporting material in the HTL layer106 and the electron-transporting material(s) in the ETL layer 110 mayinclude any suitable hole-transporter known in the art.

Compounds described herein may exhibit phosphorescence. PhosphorescentOLEDs (i.e., OLEDs with phosphorescent emitters) typically have higherdevice efficiencies than other OLEDs, such as fluorescent OLEDs. Lightemitting devices based on electrophosphorescent emitters are describedin more detail in WO2000/070655 to Baldo et al., which is incorporatedherein by this reference for its teaching of OLEDs, and in particularphosphorescent OLEDs.

An exemplary OLED is represented in FIG. 4 which depicts OLED device400. Device 400 includes substrate 402, anode 404, HTL 406, EML 408, ETL410, and cathode 412. EML 408 includes a MADF/phosphorescent donormaterial and a fluorescent emitter dispersed within a host matrix. Insuch a case where both the MADF/phosphorescent and fluorescent materialsexist within the same layer, care must be taken to avoid directformation of excitons on the fluorescent emitter (which can only harvestsinglet excitons) to ensure that all (100%) or substantially all of theelectrogenerated excitons are utilized. On the other hand, theconcentration of the fluorescent emitter must be high enough for thereto close proximity between the MADF/phosphorescent material and thefluorescent emitter so that rapid transfer from the MADF/phosphorescentdonor to the fluorescent emitter can be achieved and direct tripletemission or triplet-triplet annihilation can be avoided.

Another exemplary OLED is represented in FIG. 5, which depicts OLEDdevice 500. Device 500 includes substrate 502, anode 504, HTL 506, EML508, ETL 510, and cathode 512. EML 508 includes alternatingMADF/phosphorescent doped layers 514 and fluorescent doped layers 516.MADF/phosphorescent emitter layer 514 and fluorescent emitter layer 516alternate and are present in pairs (e.g., n pairs, where n is an integersuch as 1, 2, 3, or the like). In FIG. 5, a space is depicted betweenlayer 516 and one of layers 514 for clarity.

In some embodiments, the emissive layer includes n emitter layersincluding the fluorescent emitter and/or a host, and m donor layersincluding the MADF/phosphorescent emitter and/or a host, where n and mare integers≥1. In some implementations, n=m, n=m+1, or m=n+1. In oneembodiment, each emitter layer is adjacent to at least one donor layer.In one embodiment, each emitter layer and each donor layer furthercomprise a host. In one embodiment, each host can be the same ordifferent.

In device 500, the thickness and location of the layers must be tuned toensure that exciton formation primarily occurs in the region that isdoped with the MADF material. Furthermore, the region that contains thefluorescent doped layer should be close enough to the exciton formationzone so that the fluorescent emitters are within the distance for FRETto occur.

In some embodiments, the OLED has one or more characteristics selectedfrom the group consisting of being flexible, being rollable, beingfoldable, being stretchable, and being curved. In some embodiments, theOLED is transparent or semi-transparent. In some embodiments, the OLEDfurther comprises a layer comprising carbon nanotubes.

In some embodiments, the OLED further comprises a layer comprising adelayed fluorescent emitter. In some embodiments, the OLED comprises aRGB pixel arrangement or white plus color filter pixel arrangement. Insome embodiments, the OLED is a mobile device, a hand held device, or awearable device. In some embodiments, the OLED is a display panel havingless than 10 inch diagonal or 50 square inch area. In some embodiments,the OLED is a display panel having at least 10 inch diagonal or 50square inch area. In some embodiments, the OLED is a lighting panel.

In one embodiment, the consumer product is selected from the groupconsisting of a flat panel display, a computer monitor, a medicalmonitor, a television, a billboard, a light for interior or exteriorillumination and/or signaling, a heads-up display, a fully or partiallytransparent display, a flexible display, a laser printer, a telephone, acell phone, tablet, a phablet, a personal digital assistant (PDA), awearable device, a laptop computer, a digital camera, a camcorder, aviewfinder, a micro-display that is less than 2 inches diagonal, a 3-Ddisplay, a virtual reality or augmented reality display, a vehicle, avideo wall comprising multiple displays tiled together, a theater orstadium screen, and a sign.

In some embodiments of the emissive region, the emissive region furthercomprises a host, wherein the host comprises at least one selected fromthe group consisting of metal complex, triphenylene, carbazole,dibenzothiophene, dibenzofuran, dibenzoselenophene, aza-triphenylene,aza-carbazole, aza-dibenzothiophene, aza-dibenzofuran, andaza-dibenzoselenophene.

The organic layer(s) can also include a host. In some embodiments, twoor more hosts are preferred. In some embodiments, the hosts used maybea) bipolar, b) electron transporting, c) hole transporting or d) wideband gap materials that play little role in charge transport. In someembodiments, the host can include a metal complex. The host can be atriphenylene containing benzo-fused thiophene or benzo-fused furan. Anysubstituent in the host can be an unfused substituent independentlyselected from the group consisting of C_(n)H_(2n+1), OC_(n)H_(2n+1),OAr¹, N(C_(n)H_(2n+1))₂, N(Ar¹)(Ar²), CH═CH—C_(n)H_(2n+1),C≡C—C_(n)H_(2n+1), Ar¹, Ar¹—Ar², and C_(n)H_(2n)—Ar¹, or the host has nosubstitutions. In the preceding substituents n can range from 1 to 10;and Ar¹ and Ar² can be independently selected from the group consistingof benzene, biphenyl, naphthalene, triphenylene, carbazole, andheteroaromatic analogs thereof. The host can be an inorganic compound.For example, a Zn containing inorganic material e.g. ZnS. In someembodiments, the host comprises at least one selected from the groupconsisting of metal complex, triphenylene, carbazole, dibenzothiophene,dibenzofuran, dibenzoselenophene, aza-triphenylene, aza-carbazole,aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene.

In some embodiments, the emitting dipole of the fluorescent emitter ishorizontally oriented. In one embodiment, the ratio of organic dipolesin at least one organic layer is greater than 0.1. In one embodiment,the ratio of organic dipoles in at least one organic layer is greaterthan 0.2. In one embodiment, the ratio of organic dipoles in at leastone organic layer is greater than 0.3. In one embodiment, the ratio oforganic dipoles in at least one organic layer is greater than 0.4. Inone embodiment, the ratio of organic dipoles in at least one organiclayer is greater than 0.5. In one embodiment, the ratio of organicdipoles in at least one organic layer is greater than 0.6. In oneembodiment, the ratio of organic dipoles in at least one organic layeris greater than 0.7. In one embodiment, the ratio of organic dipoles inat least one organic layer is greater than 0.8. In one embodiment, theratio of organic dipoles in at least one organic layer is greater than0.9.

In one embodiment, the ratio of organic dipoles in at least one organiclayer is between about 0.5 and about 0.9. In one embodiment, the ratioof organic dipoles in at least one organic layer is between about 0.6and about 0.9. In one embodiment, the ratio of organic dipoles in atleast one organic layer is between about 0.7 and about 0.8. In oneembodiment, the ratio of organic dipoles in at least one organic layeris about 0.75. In one embodiment, the ratio of organic dipoles in atleast one organic layer is about 0.8.

The materials described herein as useful for a particular layer in anorganic light emitting device may be used in combination with a widevariety of other materials present in the device. For example, emissivedopants disclosed herein may be used in conjunction with a wide varietyof hosts, transport layers, blocking layers, injection layers,electrodes and other layers that may be present. The materials describedor referred to below are non-limiting examples of materials that may beuseful in combination with the compounds disclosed herein, and one ofskill in the art can readily consult the literature to identify othermaterials that may be useful in combination.

A charge transport layer can be doped with conductivity dopants tosubstantially alter its density of charge carriers, which will in turnalter its conductivity. The conductivity is increased by generatingcharge carriers in the matrix material, and depending on the type ofdopant, a change in the Fermi level of the semiconductor may also beachieved. Hole-transporting layer can be doped by p-type conductivitydopants and n-type conductivity dopants are used in theelectron-transporting layer.

Non-limiting examples of the conductivity dopants that may be used in anOLED in combination with materials disclosed herein are exemplifiedbelow together with references that disclose those materials:EP01617493, EP01968131, EP2020694, EP2684932, US20050139810,US20070160905, US20090167167, US2010288362, WO06081780, WO2009003455,WO2009008277, WO2009011327, WO2014009310, US2007252140, US2015060804,US20150123047, and US2012146012.

A hole injecting/transporting material is not particularly limited, andany compound may be used as long as the compound is typically used as ahole injecting/transporting material. Examples of the material include,but are not limited to: a phthalocyanine or porphyrin derivative; anaromatic amine derivative; an indolocarbazole derivative; a polymercontaining fluorohydrocarbon; a polymer with conductivity dopants; aconducting polymer, such as PEDOT/PSS; a self-assembly monomer derivedfrom compounds such as phosphonic acid and silane derivatives; a metaloxide derivative, such as MoO_(x); a p-type semiconducting organiccompound, such as 1,4,5,8,9,12-Hexaazatriphenylenehexacarbonitrile; ametal complex, and a cross-linkable compounds.

An electron blocking layer (EBL) may be used to reduce the number ofelectrons and/or excitons that leave the emissive layer. The presence ofsuch a blocking layer in a device may result in substantially higherefficiencies, and/or longer lifetime, as compared to a similar devicelacking a blocking layer. Also, a blocking layer may be used to confineemission to a desired region of an OLED. In some embodiments, the EBLmaterial has a higher LUMO (closer to the vacuum level) and/or highertriplet energy than the emitter closest to the EBL interface. In someembodiments, the EBL material has a higher LUMO (closer to the vacuumlevel) and/or higher triplet energy than one or more of the hostsclosest to the EBL interface. In one aspect, the compound used in EBLcontains the same molecule or the same functional groups used as one ofthe hosts described below.

The light emitting layer of the organic EL device preferably contains atleast a metal complex as light emitting material, and may contain a hostmaterial using the metal complex as a dopant material. Examples of thehost material are not particularly limited, and any metal complexes ororganic compounds may be used as long as the triplet energy of the hostis larger than that of the dopant. Any host material may be used withany dopant so long as the triplet criteria is satisfied.

One or more additional emitter dopants may be used in conjunction withthe compound of the present disclosure. Examples of the additionalemitter dopants are not particularly limited, and any compounds may beused as long as the compounds are typically used as emitter materials.Examples of suitable emitter materials include, but are not limited to,compounds which can produce emissions via phosphorescence, fluorescence,thermally activated delayed fluorescence, i.e., TADF (also referred toas E-type delayed fluorescence), triplet-triplet annihilation, orcombinations of these processes.

A hole blocking layer (HBL) may be used to reduce the number of holesand/or excitons that leave the emissive layer. The presence of such ablocking layer in a device may result in substantially higherefficiencies and/or longer lifetime as compared to a similar devicelacking a blocking layer. Also, a blocking layer may be used to confineemission to a desired region of an OLED. In some embodiments, the HBLmaterial has a lower HOMO (further from the vacuum level) and/or highertriplet energy than the emitter closest to the HBL interface. In someembodiments, the HBL material has a lower HOMO (further from the vacuumlevel) and/or higher triplet energy than one or more of the hostsclosest to the HBL interface.

Electron transport layer (ETL) may include a material capable oftransporting electrons. Electron transport layer may be intrinsic(undoped), or doped. Doping may be used to enhance conductivity.Examples of the ETL material are not particularly limited, and any metalcomplexes or organic compounds may be used as long as they are typicallyused to transport electrons.

In tandem or stacked OLEDs, the CGL plays an essential role in theperformance, which is composed of an n-doped layer and a p-doped layerfor injection of electrons and holes, respectively. Electrons and holesare supplied from the CGL and electrodes. The consumed electrons andholes in the CGL are refilled by the electrons and holes injected fromthe cathode and anode, respectively; then, the bipolar currents reach asteady state gradually. Typical CGL materials include n and pconductivity dopants used in the transport layers.

In any above-mentioned compounds used in each layer of the OLED device,the hydrogen atoms can be partially or fully deuterated. Thus, anyspecifically listed substituent, such as, without limitation, methyl,phenyl, pyridyl, etc. may be undeuterated, partially deuterated, andfully deuterated versions thereof. Similarly, classes of substituentssuch as, without limitation, alkyl, aryl, cycloalkyl, heteroaryl, etc.also may be undeuterated, partially deuterated, and fully deuteratedversions thereof.

In yet another aspect of the present disclosure, a formulation thatcomprises the novel compound disclosed herein is described. Theformulation can include one or more components selected from the groupconsisting of a solvent, a host, a hole injection material, holetransport material, and an electron transport layer material, disclosedherein.

EXPERIMENTAL EXAMPLES

The following experimental examples are provided for purposes ofillustration only, and are not intended to be limiting unless otherwisespecified. Thus, the disclosure should in no way be construed as beinglimited to the following examples, but rather, should be construed toencompass any and all variations which become evident as a result of theteaching provided herein.

Without further description, it is believed that one of ordinary skillin the art can, using the preceding description and the followingillustrative examples, make and utilize the composite materialsdisclosed herein and practice the claimed methods. The following workingexamples therefore, specifically point out the preferred embodiments ofthe present disclosure, and are not to be construed as limiting in anyway the remainder of the disclosure.

Example 1: Horizontally Oriented OLEDs

To demonstrate the utility of this disclosure, devices were made foreach general structure shown in FIG. 4 and FIG. 5. As suggested in FIG.5, devices were fabricated in the structureITO/HATCN/NPD/Tris-PCz/EML/mCBT/BPyTP/LiF/Al, where EMLs are (1) 20%PtNON:mCBP (5 nm)/10% PtNON:mCBP (5 nm)/5% PtNON:mCBP (5 nm); (2) 20%PtNON:mCBP (5 nm)/2% DABNA-2:mCBP (2 nm)/10% PtNON:mCBP (5 nm)/2%DABNA-2:mCBP (2 nm)/5% PtNON:mCBP (5 nm). As illustrated in FIGS. 7A to7D, preliminary data indicated that PtNON emitter can have a veryefficient energy transfer to DABNA-2 and such device structure canefficiently utilize the triplet excitons as well. More encouragingly,the device efficiency is also increased due to high PL efficiency andpreferred horizontally aligned fluorescent emitter DABNA-2 (indicated inFIG. 8).

Example 2

The second system of selected materials for the demonstration of thisdisclosure is the use of a t-butyl-perylene based fluorescent emitter(FLB1) and the phosphorescent platinum emitter PtNON. These materialsare selected due to the high PLQY for each and favorable overlap betweenthe PtNON emission spectrum, with emission onset as low as 430 nm, andthe absoption spectrum of FLB1. Furthermore, the advantage of theemission onset of PtNON at a much higher energy than the roomtemperature peak emission wavelength (˜500 nm) and the fact that thereis very little stokes shift in the FLB1 emitter will result in anemission primarily from the fluorescent emitter that is remarkably bluerthan that of the phosphorescent emitter alone. Further materialsoptimization of a narrow blue emitters may further enhance this effect.

Devices were made for each general structure shown in FIG. 4 and FIG. 5.For the first case (FIG. 4) devices were fabricated in the structureITO/HATCN(10 nm)/NPD (40 nm)/TAPC (10 nm)/26mCPy: 10% PtNON:x % FLB1 (25nm)/DPPS (10 nm)/BmPyPB(40 nm)/LiF/Al where HATCN is1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile, NPD isN,N′-diphyenyl-N,N′-bis(1-naphthyl)-1,1′-biphenyl-4,4″-diamine, TAPC isdi-[4-(N,N-di-toylyl-amino)-phyenyl]cyclohexane, 26mCPy is2,6-bis(N-carbazolyl) pyridine, DPPS isdiphenyl-bis[4-(pyridin-3-yl)phenyl]silane, and BmPyPB is1,3-bis[3,5-di(pyridin-3-yl)phenyl]benzene.

As shown in FIGS. 9A to 9D, when PtNON devices were doped with a smallamount of FLB1 (1% or 2%) the emission originated nearly exclusivelyfrom the fluorescent emitter. Furthermore, the moderate external quantumefficiencies (EQE) of 10-15% indicate that a large portion of theelectrogenerated excitons are being harvested, assuming a 100% electronto photon conversion efficiency corresponds to an EQE of 20-30° % due tooutcoupling losses. When considering both of these results, it is clearthat exciton are being formed on the phosphorescent PtNON molecules, asevidenced by the high efficiencies, which then transfer to thefluorescent FLB1 emitter via FRET as evidenced by the nearly exclusivefluorescent emission. It also appears that there is a crucial controlover the FLB1 necessary since the efficiency drops rapidly withincreasing concentration. This is attributed to the direct formation ofexcitons on the fluorescent dopant, possibly due to charge trapping assuggested by the change in current-voltage characteristics althoughother mechanisms for losses may exist.

To circumvent any potential tradeoff between high FRET efficiency andefficiency losses from direct exciton formation on FLB1 molecules, thesecond strategy (FIG. 4) was developed. Devices were fabricated in thestructure ITO/HATCN(10 nm)/NPD (40 nm)/TAPC (10 nm)/26mCPy: 10% PtNON (4nm)/26mCPy:2% FLB1 (2 nm)/26mCPy:10% PtNON (4 nm)/26mCPy:2% FLB1 (2nm)/26mCPy:10% PtNON (4 nm)/DPPS (10 nm)/BmPyPB(40 nm)/LiF/Al. In thisstructure, alternating phosphorescent and fluorescent doped layers wereused. This order was selected so that the recombination zone, whichtypically resides near one of the charge blocking layers due topotential charge imbalances, is located on the PtNON doped layer so thatthe majority of the excitons are formed on the PtNON molecules which canharvest 100% of the electrogenerated excitons. The layer thicknesseswere also kept low so that there was a sufficiently small distancebetween the phosphorescent material and the fluorescent emitters so thatrapid FRET could occur. As shown in FIG. 10A to 10D, this device showedmuch higher efficiency over 20% while still exhibiting emissionprimarily originating from the fluorescent emitter indicating theutility of the devices/compositions disclosed herein to manipulate theemission spectrum and emit nearly exclusively from fluorescent emitterswhile maintaining a high efficiency.

The disclosures of each and every patent, patent application, andpublication cited herein are hereby incorporated herein by reference intheir entirety. While this disclosure refers to specific embodiments, itis apparent that other embodiments and variations of this disclosure maybe devised by others skilled in the art without departing from the truespirit and scope of the disclosure. The appended claims are intended tobe construed to include all such embodiments and equivalent variations.

We claim:
 1. An organic light emitting device (OLED) comprising: ananode; a cathode; and at least one organic layer disposed between theanode and the cathode; wherein the at least one organic layer includes aphosphorescent/MADF emitter and a fluorescent emitter.
 2. The OLED ofclaim 1, wherein the phosphorescent/MADF emitter and a fluorescentemitter exist in a single layer which further comprises a host matrix.3. The OLED of claim 1, wherein the at least one organic layer is anemissive layer comprising n emitter layers including the fluorescentemitter, and m donor layers including the MADF/phosphorescent emitter;wherein n and m are integers; wherein each emitter layer is adjacent toat least one donor layer; wherein each emitter layer and each donorlayer further comprise a host; and wherein each host can be the same ordifferent.
 4. The OLED of claim 3, wherein n=m, n=m+1, or m=n+1.
 5. TheOLED of claim 3, wherein the phosphorescent/MADF emitter is a compoundhaving Formula I or Formula II;

wherein A is an accepting group comprising one or more of the followingstructures, which can optionally be substituted:

wherein D is a donor group comprising of one or more of the followingstructures, which can optionally be substituted:

wherein C in Formula I or Formula II comprises one or more of thefollowing structures, which can optionally be substitute d:

wherein N in Formula I or II comprises one or more of the followingstructures, which can optionally be substituted:

wherein each of a⁰, a¹, and a² independently is present or absent, andif present, comprises a direct bond and/or linking group comprising oneor more of the following:

wherein each occurrence of a is independently substituted orunsubstituted N or substituted or unsubstituted C; wherein b¹ and b²independently is present or absent, and if present, comprises a linkinggroup comprising one or more of the following:

wherein each occurrence of X is independently B, C, N, O, Si, P, S, Ge,As, Se, Sn, Sb, or Te; wherein Y is O, S, S═O, SO₂, Se, N, NR³, PR³,RP═O, CR^(i)R², C═O, SiR¹R², GeR¹R², BH, P(O)H, PH, NH, CR¹H, CH², SiH²,SiHR¹, BH, or BR³, wherein each of R, R¹, R², and R³ independently ishydrogen, aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl,alkyl, alkenyl, alkynyl, deuterium, halogen, hydroxyl, thiol, nitro,cyano, amino, a mono- or di-alkylamino, a mono- or diaryl amino, alkoxy,aryloxy, haloalkyl, aralkyl, ester, nitrile, isonitrile, alkoxycarbonyl,acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino,sulfamoyl, carbamoyl, alkylthio, sulfinyl, ureido, phosphoramide,mercapto, sulfo, carboxyl, hydrazino, substituted silyl, orpolymerizable, or any conjugate or combination thereof, wherein n is anumber that satisfies the valency of Y; and wherein M is platinum,palladium, nickel, manganese, zinc, gold, silver, copper, iridium,rhodium, and/or cobalt.
 6. The OLED of claim 5, wherein a² is absent inFormula I.
 7. The OLED of claim 5, wherein a² and b² are absent inFormula I or Formula II.
 8. The OLED of claim 5, wherein A is

a² and b² are absent; and D is


9. The OLED of claim 5, wherein C in Formula I or Formula II is


10. The OLED of claim 5, wherein N in Formula I or Formula II issubstituted or unsubstituted


11. The OLED of claim 5, wherein the compound having Formula I orFormula II is a compound having Formula III;

wherein M is Ir, Rh, Mn, Ni, Cu, or Ag; wherein each of R¹ and R²independently are hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, nitro hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein each of Y^(1a) and Y^(1b) independently is O, NR²,CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof,wherein each of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure; whereineach of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N orCR^(6a), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; each of Y^(3a), Y^(3b), Y^(3c), Y^(3d),Y^(4a), Y^(4b), Y^(4c), and Y^(4d) independently is N, O, S, NR^(6a),CR^(6b), or Z(R^(6c))₂, wherein each of R^(6a) and R^(6b) isindependently hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein Z is C or Si, and wherein each R^(6c) independentlyis hydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene; whereineach of m and n independently is an integer of 1 or 2; wherein each of

independently is partial or full unsaturation of the ring with which itis associated.
 12. The OLED of claim 5, wherein the compound havingFormula I or Formula II is a compound having Formula IV;

wherein M is Pt, Pd and Au; wherein each of R¹ and R² independently ishydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, nitrohydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene;wherein each of Y^(1a) and Y^(1b) independently is O, NR², CR²R³, S,AsR², BR², PR², P(O)R², or SiR²R³, or a combination thereof, whereineach of R² and R³ independently is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, arylalkene, or R² and R³ together form C═O,wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure; whereineach of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N orCR^(6b), wherein R^(6a) is hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; wherein each of Y^(3a), Y^(3b), Y^(3c),Y^(3d), Y^(3e), Y^(3f), Y^(4a), Y^(4b), Y^(4c), and Y^(4d) independentlyis N, O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂, wherein each of R^(6a) andR^(6b) is independently hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; wherein Z is C or Si, and wherein each R^(6c)independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein each of m is an integer of 1 or 2; and wherein eachof

independently is partial or full unsaturation of the ring with which itis associated.
 13. The OLED of claim 5, wherein the compound havingFormula I or Formula II is a compound having Formula V;

wherein M is Pt, Pd, Au, Ag; wherein each of R¹ and R² independently arehydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, nitrohydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene;wherein one of Y^(1a) and Y^(1b) is B(R²)₂ and the other of Y^(1a) andY^(1b) is O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or acombination thereof, wherein each of R² and R³ independently ishydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³together form C═O, wherein each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure; wherein each of Y^(2a), Y^(2b) Y^(2c) and Y^(2d)independently is N or CR^(6a), wherein R^(6a) is hydrogen, substitutedor unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein each of Y^(3a), Y^(3b),Y^(3c), Y^(3d), Y^(4a), Y^(4b), Y^(4c), and Y^(4d) independently is N,O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂, wherein each of R^(6a) and R^(6b)is independently hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein Z is C or Si, and wherein each R^(6c) independentlyis hydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, or arylalkene; whereineach of m and n independently are an integer 1 or 2; wherein each of

independently is partial or full unsaturation of the ring with which itis associated.
 14. The OLED of claim 5, wherein the compound havingFormula I or Formula II is a compound having Formula VI;

wherein M is Pt, Pd, Ir, Rh, or Au; wherein each of R¹ and R²independently are hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, nitro hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein each of Y^(1a), Y^(1b), and Y^(1c) independently isO, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, or a combinationthereof, wherein each of R² and R³ independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³ together formC═O, wherein each of R² and R³ independently is optionally linked to anadjacent ring structure, thereby forming a cyclic structure; whereineach of Y^(2a), Y^(2b), Y^(2c), and Y^(2d) independently is N, NR^(6a),or CR^(6b), wherein each of R^(6a) and R^(6b) independently is hydrogen,substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio,alkoxy, haloalkyl, arylalkane, or arylalkene; wherein each of Y^(3a),Y^(3b), Y^(3c), Y^(3d), Y^(3e), Y^(4a), Y^(4b), Y^(4c), and Y^(4d)independently is N, O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂, wherein eachof R^(6a) and R^(6b) is independently hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein Z is C or Si, and whereineach R^(6c) independently is hydrogen, substituted or unsubstitutedalkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; wherein each of m and n independently are aninteger 1 or 2; wherein each of

independently is partial or full unsaturation of the ring with which itis associated.
 15. The OLED of claim 5, wherein the compound havingFormula I or Formula II is a compound having Formula VII;

wherein M comprises Ir, Rh, Pt, Os, Zr, Co or Ru; wherein each of R¹ andR² independently are hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, nitro hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; wherein each of Y^(1a), Y^(1c) and Y^(1d)independently is O, NR², CR²R³, S, AsR², BR², PR², P(O)R², or SiR²R³, ora combination thereof, wherein each of R² and R³ independently ishydrogen, substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl,heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, hydroxyl,halogen, thio, alkoxy, haloalkyl, arylalkane, arylalkene, or R² and R³together form C═O, wherein each of R² and R³ independently is optionallylinked to an adjacent ring structure, thereby forming a cyclicstructure; wherein Y^(1e) is present or not present; wherein when Y^(Le)is present, Y^(Le) represents O, NR², CR²R³, S, AsR², BR², PR², P(O)R²,or SiR²R³, or a combination thereof; wherein each of R² and R³independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane,arylalkene, or R² and R³ together form C═O, wherein each of R² and R³independently is optionally linked to an adjacent ring structure,thereby forming a cyclic structure; wherein when Y^(1e) is not present,Y^(1e) represents no bond; wherein each of Y², Y^(2b) Y^(2c), and Y^(2d)independently is N or CR^(6a), wherein R^(a) is hydrogen, substituted orunsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane,cycloalkane, heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy,haloalkyl, arylalkane, or arylalkene; wherein each of Y^(3a), Y^(3b),Y^(3c), Y^(3d), Y^(3e), Y^(4a), Y^(4b), Y^(4c), and Y^(4d) independentlyis N, O, S, NR^(6a), CR^(6b), or Z(R^(6c))₂, wherein each of R^(6a) andR^(6b) is independently hydrogen, substituted or unsubstituted alkyl,alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane,heterocyclyl, amino, hydroxyl, halogen, thio, alkoxy, haloalkyl,arylalkane, or arylalkene; wherein Z is C or Si, and wherein each R^(6c)independently is hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene; wherein in each of each of Y^(5a), Y^(5b), Y^(5c), Y^(5d),Y^(6a), Y^(6b), Y^(6c), and Y^(6d) independently is N, O, S, NR^(6a), orCR^(6b); wherein each of m, n, l and p independently is an integer of 1or 2; wherein each of

independently is partial or full unsaturation of the ring with which itis associated.
 16. The OLED of claim 1, wherein the fluorescent emitteris selected from the following:
 1. Aromatic Hydrocarbons and TheirDerivatives


2. Arylethylene, Arylacetylene and Their Derivatives


3. Heterocyclic Compounds and Their Derivatives


4. Other fluorescent luminophors

wherein each of R¹¹, R²¹, R³¹, R⁴¹, R⁵¹, R⁶¹, R⁷¹ and R⁸¹ independentlyrepresents hydrogen, aryl, cycloalkyl, cycloalkenyl, heterocyclyl,heteroaryl, alkyl, alkenyl, alkynyl, deuterium, halogen, hydroxyl,thiol, nitro, cyano, amino, a mono- or di-alkylamino, a mono- ordiarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, nitrile,isonitrile, heteroaryl, alkoxycarbonyl, acylamino, alkoxycarbonylamino,aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio,sulfinyl, ureido, phosphoramide, mercapto, sulfo, carboxyl, hydrazino,substituted silyl, polymeric, or any conjugate or combination thereof.wherein each of Y^(a), Y^(b), Y^(c), Y^(d), Y^(e), Y^(f), Y^(g), Y^(h),Y^(i), Y^(j), Y^(k), Y^(l) Y^(m), Y^(n), Y^(o) and Y^(p) independentlyrepresents C, N or B; and wherein each of U^(a), U^(b) and Uindependently represents CH₂, CR¹R², C═O, CH₂, SiR¹R², GeH₂, GeR¹R², NH,NR³, PH, PR³, R³P═O, AsR³, R³As═O, O, S, S═O, SO₂, Se, Se═O, SeO₂, BH,BR³, R³Bi═O, BiH, or BiR³; wherein each of R¹, R², and R³ independentlyrepresents hydrogen, substituted or unsubstituted alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl,amino, nitro hydroxyl, halogen, thio, alkoxy, haloalkyl, arylalkane, orarylalkene.
 17. The OLED of claim 1, wherein the phosphorescent/MADFemitter is PtNON;


18. The OLED of claim 1, wherein the fluorescent emitter is DABNA-2


19. The OLED of claim 1, wherein the emitting dipole of the fluorescentemitter is horizontally oriented.
 20. The OLED of claim 1, wherein theratio of organic dipoles in at least one organic layer is greater than0.7.